River bank instability from unsustainable sand mining in the lower Mekong River
River bank instability from unsustainable sand mining in the lower Mekong River
Recent growth of the construction industry has fuelled the demand for sand, with considerable volumes being extracted from the world’s large rivers. Sediment transport from upstream naturally replenishes sediment stored in river beds, but the absence of sand flux data from large rivers inhibits assessment of the sustainability of ongoing sand mining. Here, we demonstrate that bedload (0.18 ± 0.07 Mt yr
−1) is a small (1%) fraction of the total annual sediment load of the lower Mekong River. Even when considering suspended sand (6 ± 2 Mt yr
−1), the total sand flux entering the Mekong delta (6.18 ± 2.01 Mt yr
−1) is far less than current sand extraction rates (50 Mt yr
−1). We show that at these current rates, river bed levels can be lowered sufficiently to induce river bank instability, potentially damaging housing and infrastructure and threatening lives. Our research suggests that on the Mekong and other large rivers subject to excessive sand mining, it is imperative to establish regulatory frameworks that limit extraction rates to levels that permit the establishment of a sustainable balance between the natural supply/storage of sand and the rate at which sand is removed.
217-225
Hackney, Christopher
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Darby, Stephen
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Parsons, Daniel
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Leyland, Julian
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Best, James
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Aalto, Rolf
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Nicholas, Andrew
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Houseago, Robert
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1 March 2020
Hackney, Christopher
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Darby, Stephen
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Parsons, Daniel
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Leyland, Julian
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Best, James
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Aalto, Rolf
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Nicholas, Andrew
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Houseago, Robert
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Hackney, Christopher, Darby, Stephen, Parsons, Daniel, Leyland, Julian, Best, James, Aalto, Rolf, Nicholas, Andrew and Houseago, Robert
(2020)
River bank instability from unsustainable sand mining in the lower Mekong River.
Nature Sustainability, 3 (3), .
(doi:10.1038/s41893-019-0455-3).
Abstract
Recent growth of the construction industry has fuelled the demand for sand, with considerable volumes being extracted from the world’s large rivers. Sediment transport from upstream naturally replenishes sediment stored in river beds, but the absence of sand flux data from large rivers inhibits assessment of the sustainability of ongoing sand mining. Here, we demonstrate that bedload (0.18 ± 0.07 Mt yr
−1) is a small (1%) fraction of the total annual sediment load of the lower Mekong River. Even when considering suspended sand (6 ± 2 Mt yr
−1), the total sand flux entering the Mekong delta (6.18 ± 2.01 Mt yr
−1) is far less than current sand extraction rates (50 Mt yr
−1). We show that at these current rates, river bed levels can be lowered sufficiently to induce river bank instability, potentially damaging housing and infrastructure and threatening lives. Our research suggests that on the Mekong and other large rivers subject to excessive sand mining, it is imperative to establish regulatory frameworks that limit extraction rates to levels that permit the establishment of a sustainable balance between the natural supply/storage of sand and the rate at which sand is removed.
Text
Hackney et al manuscript ACCEPTED
- Accepted Manuscript
More information
Accepted/In Press date: 18 November 2019
e-pub ahead of print date: 13 January 2020
Published date: 1 March 2020
Additional Information:
Funding Information:
This study was supported by awards NE/JO21970/1, NE/JO21571/1 and NE/JO21881/1 from the UK Natural Environment Research Council (NERC). We thank the Mekong River Commission for access to hydrological and suspended sediment data, and the Department of Hydrology and River Works in Cambodia for logistical support and help in the field. J.L.B. was in receipt of a University of Southampton Diamond Jubilee International Visiting Fellowship that aided the completion of this work.
Publisher Copyright:
© 2020, The Author(s), under exclusive licence to Springer Nature Limited.
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Local EPrints ID: 436012
URI: http://eprints.soton.ac.uk/id/eprint/436012
ISSN: 2398-9629
PURE UUID: 390c0f57-0636-42bc-b70f-ed176bcdac0d
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Date deposited: 26 Nov 2019 17:30
Last modified: 17 Mar 2024 05:04
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Author:
Christopher Hackney
Author:
Daniel Parsons
Author:
James Best
Author:
Rolf Aalto
Author:
Andrew Nicholas
Author:
Robert Houseago
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